As system clock speeds continue to rise, signal reliability and accuracy have become increasingly important, particularly with respect to amplitude, frequency, and distortion. Providing signals with robust duty cycles has also been desirable, as many digital circuits require a precisely controlled duty cycle for proper operation. In some cases, circuits are configured to operate on both rising and falling edges of clocks, further emphasizing the importance of maintaining a consistently accurate duty cycle for a clock signal.
Known approaches for correcting duty cycle error and providing duty cycle corrected clock signals (e.g., a clock signal having a 50% duty cycle) typically utilize adjustable delay circuits that are incrementally adjusted until the duty cycle of a clock signal is corrected. The adjustable delay circuits may be repeatedly adjusted until any detectable duty cycle error in an output clock signal is eliminated. The process of correcting the duty cycle can take a relatively long time, as the iterative adjustment of the delays and duty cycle error detection can take several hundreds of clock cycles to fully correct duty cycle error. Such approaches may be unable to correct duty cycle error as quickly as may be desired. For example, operation of the circuits relying on the duty cycle corrected clock signal may not begin until the duty cycle error is corrected. As a result, several hundreds of clock cycles must elapse before any of these circuits may be operated, which can be undesirable in many applications.